Gas prices have increased throughout the holiday season, and drivers are now being warned of prices as high as $5 per gallon in coming years.

"By Nov. 2012, if we stay on the path that we're on, just in time for the presidential election, American voters will pay $5 a gallon for gasoline," former Shell Oil president John Hofmeister predicted earlier this week.

Soaring gas prices are already causing dismay, as they hit during some of the busiest travel times of the year.

"This is sort of unprecedented in the U.S. to see a spike at this time of the year," Edmunds.com executive director Paul Seredynski said.

Gas prices have hiked to more than $3 a gallon -- 76 percent higher than 2008.

"We're turning in the rental car early and switching to taxis and the Metro for the rest of the visit," one Washington, D.C., visitor said.

"Hurts a lot in the pocket," another traveler added.

There are signs of economic recovery, and the much-needed return of robust consumer spending, but persistently higher gas prices could kill those gains.

"It's almost like a 'prozac' for the country when gas prices are low," Seredynski said. "People tend to feel better about the economy. They feel more mobile. They feel they have more additional income to spend on other things."

There's no sign of gas prices falling anytime soon. Oil supply isn't going up, but the demand is increasing by billions of gallons.

"It's like we're watching a hurricane coming at us and not doing anything about it," Hofmeister explained.